let obj1_A = {
    name: "小明",
    age: 2,
    findChild(father, age) {
        return father + age;
    }
};
obj1_A.findChild(obj1_A.name, obj1_A.age);
let obj2_A = {
    name: "小明"
};
let obj3_A = {
    name: "小明",
    gender: "112233"
};
let obj4_A = {
    name: "老皮",
    id: 33
};
// 只读属性：错误示例
// 只读属性只能在定义时赋值, 无法二次赋值
// obj4_A.id = 55
